A Li/1 M LIClO4 in propylene carbonate (PC)/Li8Mn2O4 cell is used to investigate the influence of side reactions on the current-potential behavior of intercalation electrodes. Slow cyclic voltammograms and self-discharge data are combined to estimate, simultaneously, the reversible potential vs state-of-charge curve for the host material and the kinetic parameters for the side reaction. This information is then used, together with estimates of the solid-state diffusion coefficient and main reaction exchange current density, in a mathematical model of the system. Predictions from the model compare favorably with continuous cycling results and galvanostatic experiments with periodic current interruptions.